"They promised me you wouldn't do this to me," Aniston, 40, told DeGeneres after revealing that she is learning to sing and play a dobro for an upcoming film role. But despite her protests, Aniston belted out a few bars of the George Gershwin standard "I've Got a Crush on You," then retorted, "I'm absolutely mortified that you did that to me."

Ellen's verdict? "I would put you through to the next round," DeGeneres said, referencing her new gig as an American Idol judge.

And the talk show host was equally probing when it came to Aniston's least favorite subject – her dating life. When DeGeneres noted, "They're always saying you're devastated. You don't look devastated," Aniston responded: "I know. I don't know how I get that end of the story every time."

"I have to talk to those people ... that are writing up those stories," Aniston said, joking that it was her former boyfriends who should be cast as the devastated ones in the gossip pages.

"Yeah, change it around," DeGeneres said to applause. "They're getting the raw end of the deal losing her. What's wrong with people?"